ECOMORPHOLOGY OF FRESH-WATER FISHES

Strong relationships between basic form and ecological function in fishes allow the comparative study of ecological relationships using morphological features. Within-fauna variation and between-fauna similarities of ecomorphological characteristics of freshwater fish assemblages from five regions around the world were compared and contrasted. Ecomorphological features allowed identification of a number Of ecologically convergent species from different regions. Based on a relative scale of convergence, tropical fish assemblages exhibited a greater degree of ecological convergence than temperate assemblages. The ecomorphological comparison supports the view that biotic interactions have a greater relative influence on evolution in the tropics compared with temperate regions.